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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 241142
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
742 AM EDT Sat Jun 24 2017

.SYNOPSIS...
A cold front is crossing the region early this morning. High
pressure will build back into the region later today. Additional
weak cold fronts will cross the region Sunday through Tuesday,
but with little if any precipitation. High pressure will cross
the region Wednesday and then settle over the western Atlantic
Ocean late in the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Initial boundary associated with the remnant circulation of
Cindy is crossing the region with a squall line at this time.
Not much depth to the line but a rumble of thunder can`t be
ruled out, along with a brief wind gust to around 40 mph and
brief blinding downpour. After the line and front clears the
area, northwest flow will start bringing drier air into the
region. All showers should clear the area before midday, with
midday and afternoon turning out mostly sunny. Temperatures will
still be quite warm with good mixing behind the front, so still
expecting highs well into the 80s, with 90 possible in the warm
spots. However, dew points will generally be sliding downward,
so it won`t feel as oppressive.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
The remainder of the short term will feature an upper trough
settling over the Great Lakes, and surface high pressure over
the central US. Northwest surface flow and passing disturbances
aloft will bring weak reinforcing cold fronts southwest across
the area. With much drier air in place, little if any precip is
expected with these fronts, though an isolated shower or t-storm
can`t be completely ruled out, especially Monday and Monday
night as a little more forcing is present aloft. Otherwise,
temperatures will be sliding downward each day, with low-mid 80s
Sunday and upper 70s to low 80s Monday. Lows will decline in a
similar fashion, with low-mid 60s common tonight, upper 50s to
low 60s more likely Sunday night, and mid-upper 50s more common
Monday night.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Cool (for late June) weather to start the long term as an upper
trough starts sliding east across the region and high pressure
to our west keeps a cool northwest flow in place. The passing
trough may result in enough instability to result in a stray
shower or t-storm Tuesday, but most spots stay dry. The trough
starts moving east away from us Wednesday, with ridging building
in from the southwest late in the week as the surface high
pushes east and sets up shop off the coast (i.e. a Bermuda
high). This will result in temperatures starting to warm back
above normal by the end of the week, and an increasing risk of
diurnal terrain showers and storms in the mountains by Friday.

&&

.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
Variable conditions this morning as cold front and squall line
moves through. Occasional IFR with heavy rain and gusty winds to
35 knots possible as cold front passes. After it is through,
generally expect VFR through remainder of forecast period, with
winds diminishing, especially tonight. An isolated thunderstorm
could occur Monday or Tuesday with a weak reinforcing cold front
and following upper trough, but odds are low.

&&

.MARINE...
-- Changed Discussion --
High pressure building in behind a cold front should continue
to cause sporadic SCA gusts today, but odds of continued SCA
winds beyond this afternoon, while not negligible, look low, and
therefore have not extended headlines any further. Will need to
watch for potential mixing and resulting SCA gusts Sunday and
Monday with multiple weak reinforcing cold fronts moving
through, however. Otherwise, mainly dry through the rest of the
forecast period, with just an isolated thunderstorm possible
Monday or Tuesday with a weak front and following trough.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
-- Changed Discussion --
Coastal flood advisories up for several portions of our upper
bay shore along with the DC waterfront right now thanks to
persistent southerly flow and above normal astronomical tides.
This should be a one-cycle event, however, since northwest winds
are already enveloping the region behind the approaching cold
front. Water levels should stay below minor flood thresholds for
the foreseeable future after this morning`s high tide.
-- End Changed Discussion --

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...Coastal Flood Advisory until 10 AM EDT this morning for DCZ001.
MD...Coastal Flood Advisory until 8 AM EDT this morning for MDZ018.
     Coastal Flood Advisory until 10 AM EDT this morning for MDZ014.
     Coastal Flood Advisory until 11 AM EDT this morning for MDZ011.
     Coastal Flood Advisory until 1 PM EDT this afternoon for
     MDZ508.
VA...Coastal Flood Advisory until 10 AM EDT this morning for VAZ054.
WV...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for
     ANZ530>543.
-- End Changed Discussion --

&&

$$
SYNOPSIS...RCM
NEAR TERM...RCM
SHORT TERM...RCM
LONG TERM...RCM
AVIATION...RCM
MARINE...MM/RCM
TIDES/COASTAL FLOODING...RCM